Green Infrastructure

Green infrastructure or green solutions uses natural systems and/or engineered systems designed to mimic natural processes to more effectively manage urban stormwater and reduce receiving water impacts. These systems are often soil or vegetation-based and include planning approaches such as tree preservation and impervious cover reduction, as well as structural interventions such as rain gardens and permeable pavements. By maintaining or restoring the hydrologic function of urban areas, green infrastructure treats precipitation as a resource rather than a waste, and can play a critical role in achieving community development as well as water quality goals.

The City of Omaha Stormwater Program, a comprehensive program comprised of various elements and activities designed to reduce stormwater pollution to the Maximum Extent Practicable (MEP).The Stormwater Program is focused on eliminating prohibited non-stormwater discharges through a National Pollutant Discharge Elimination System (NPDES) municipal stormwater discharge permit. To learn more about Omaha's Stormwater Program, visit their website here.

What is the City Doing?

A CSO Green Solutions Program has been established to implement stormwater best management practices (BMPs). The City is currently working on:

Changing City Policies and Goals to Incorporate Green Solutions

The City continues to develop criteria or procedures to be used to include Green Solutions in CSO related projects.

Implementing a Public Education Program

The City will continue to educate the general public about what it can to do reduce its own impact on the combined sewer system. This will likely include the use of rain barrels, onsite infiltration of stormwater, and similar controls. The City has retained the services of a Public Participation Facilitator who will assist with this effort.

An important element of the City’s Long Term Control Plan will be the continued operation of programs that have been implemented. This includes the implementation of the City’s Municipal Separate Stormwater Sewer System (MS4) permit. These programs assist the City in reducing the amount of pollutants entering the sewer system or receiving streams through contaminated stormwater or combined flows. These controls are not implemented solely in the combined sewer system service areas but across Omaha and the greater metropolitan area.

The City is a member of the Papillion Creek Watershed Partnership, a consortium representing nine communities, two counties, and a natural resource district. The partnership developed six strategies that addressed water quality and water quantity management issues, and were adopted as the Stormwater Element of the City’s Master Plan in the summer of 2006. The policies cover stormwater management financing, peak flow reduction, pollution, landscape preservation, restoration and conservation, erosion and sediment control, and flood plain management. To see what the City is doing to meet these six policies visit the City of Omaha Stormwater Program.

What Can I Do?

Green Solutions for the typical home site capture stormwater runoff before it enters the sewer system.

Rain Gardens

Rain gardens contain flowering plants and grasses (preferably native species of both) that can survive in soil soaked with water from rain storms. However, they are not gardens that have standing water. Rain gardens collect and slow stormwater runoff and increase its infiltration into the soil. They reduce the rapid flow of stormwater from homes and businesses to storm drains and thus protect streams and lakes from pollutants that are washed from house roofs and paved areas and from channel and bank erosion.

Rain barrels, also called cisterns, are aboveground water storage containers that capture rain runoff from a building's roof using the gutter and downspout system.

Use of a rain barrel located under gutter downspouts and connected with a hose to the rain garden can help spread rainfall over longer periods of time, thereby slowing the flow of stormwater and increasing its infiltration. For these to be effective, it is necessary that the water collected be used on site and not allowed to flow into the stormwater system.

Directing runoff from roof drains and impervious surfaces to vegetated areas allows the water to infiltrate, thus resulting in decreases of peak flows downstream. In the CSO area, this is probably the most significant thing that citizens can do to control CSOs. Disconnection of roof drains from the sanitary or combined sewer system will assist in preventing heavy rain and stormwater from overwhelming these systems, resulting in environmental pollution and property damage.

Bioswales are stormwater runoff conveyance systems that provide an alternative to storm sewers. They can absorb low flows or carry runoff from heavy rains to storm sewer inlets or directly to surface waters. Bioswales improve water quality by infiltrating the first flush of storm water runoff and filtering the large storm flows they convey.

The majority of annual precipitation comes from frequent, small rain events. Much of the value of bioswales comes from infiltrating and filtering nearly all of this water.

Bioretention Basins

A bioretention area is a shallow, planted area designed to retain or detain stormwater before it is infiltrated or discharged downstream. While bioretention areas are sometimes called “rain gardens” that term is usually used to describe a planted area on an individual homeowner’s lot. Bioretention basins serve the same purpose but usually apply to larger projects in community common areas and oftentimes in non-residential areas.